Development of atomic layer deposition-activated microchannel plates for single particle detection at cryogenic temperatures

• Published in: Journal of vacuum science & technology. A, Vacuum, surfaces, and films Vacuum, surfaces, and films, 2014-03, Vol.32 (2)
• Main Authors: Gorelikov, Dmitry, Sullivan, Neal, de Rouffignac, Philippe, Li, Huazhi, Narayanamoorthy, Jayasri, Tremsin, Anton S.
• Format: Article
• Language: English
• Subjects: ADHESION; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COUNTING RATES; CRYOGENICS; DEPOSITION; DETECTION; ELECTRON EMISSION; GLASS; MICROCHANNEL ELECTRON MULTIPLIERS; PARTICLES; SUBSTRATES; TIME RESOLUTION
• ISSN: 0734-2101; 1520-8559
• DOI: 10.1116/1.4862947

Atomic layer deposition (ALD) technology is used to nanoengineer functional films inside the pores of microchannel plate (MCP) electron multipliers, enabling a novel MCP manufacturing technology that substantially improves performance and opens novel applications. The authors have developed custom tools and recipes for the growth of conformal films, with optimized conductance and secondary electron emission inside very long channels (∼6–20 μm diameter and >600 μm length, with tens of millions of channels per single MCP) by ALD. The unique ability to tune the characteristics of these ALD films enables their optimization to applications where time-resolved single particle imaging can be performed in extreme conditions, such as high counting rates at cryogenic temperatures. Adhesion of the conductive and emissive nanofilms to the 20 μm pore MCP glass substrates and their mechanical stability over a very wide range of temperatures (10–700 K) were confirmed experimentally. Resistance of ALD MCPs was reproducible during multiple cool-down cycles with no film degradation observed. Optimizing resistance of novel MCPs for operation at cryogenic temperature should enable high count rate event detection at temperatures below 20 K.